Folding pencil compass



June 26 1928. I 1,674,726

A. J. KEANEY FOLDING PENCIL COMPAS S Filed Sept. 5, 1926 IN V EN TOR.

1m; Jlfiwwg, BY 2 2 'C ETORNEYSf Patented June 26, 1928.

ALLAN J. KEANEY, OFBROOKLYN, NEW YORK.

I FOLDING PENCIL COMPASS.

' Application'filed September 3, 1926. Serial No. 133,332.

This inventionrelates, generally, to improvements in folding pencil compasses of the type and kind shown in my United States Letters Patent, No.-1,611,835, Dec. 21, 1926, and which consists in a pencil leg or body, having at one end an adjustable lead carrying and holding means, and with the opposite end of which is 'pivotally connected a foldable compass leg adapted to be folded into and concealed within the pencil leg when not in use, whereby the latter possesses the appearance and may be employed as an ordinary pencil. I This invention-has for its principal object to improve the general arrangement and construction of folding pencil compasses of the kind above. mentioned, and especially to improve the construction of the pivotingconnection between the pencil leg and the compass leg to provide a simple and effective means for frictionally-binding the legs, when opened out andfadjusted for use as a compass, to holdthe same against displacement from such adjusted positions when so using the device.

Theinvention has for provide detail improvements in the construction of the foldable compass leg, audespecially in connection with the joint or articulation connecting -themembers of'said, compass leg. g

Other objects of this invention, not at this time more particularly enumerated, will be clearly understood from the following detailed descriptionof the same The invention is clearly illustrated in'the accompanying drawings, in which Figurel is a side elevation of my im proved folding pencil compass in its folded condition; Figure 2 is a face view of the same in its foldedcondition: Figure 3 is a longitudinal section, the. same showing the first step in unfolding the foldable leg thereof and Figure 4 is a side elevation of the f same with the foldable legfcompletely .un-

folded, extended and adjusted ready for use.

Figure 5 is 'anenlarged fragmentary side View of the pencil compass, illustrating the novel construction of'the frictional binding or locking structure for holdingthe extended and spread legs in desired adjusted position during use of the device as a compass Figure 6 is an enlarged fragmentary plan view of a, novel frictional joint uniting. the foldable sections of the foldable compass leg a further object to of the device, as disposed when said sections are folded together; Figure 7 is a similar view with the sections shown unfolded and extended; and Figure 8 is a bottom plan view with said sections show-n unfolded and extended.

Similar characters of reference are employed in all of the hereinabove described views to indicate corresponding parts. I

Referring now to said drawings, the refer ence character 10 indicates the pencil leg or body of the device, the same consisting in a tubular metallic body portion, having at one end bifurcated bearing blockll providing a central hearing or joint slot 12. Said body portion 10 is provided, in downward extension from said bearing or jointslot 12, with g a longitudinal opening 13 giving lateralaccess intothe interior thereof.

The reference character 14 indicates a lead holding shell having a tapered free end portion 15 through which a pencil lead 16 may be operatively' projected. Said shell 14 is provided atits innerend with a reduced extension17 adapted to telescope into the free. end of said pencil body portion 10, and so as to turn axially relative thereto. Internally disposed and axially aligned in connectionwith said shell 14 is a fixed sleeve 18 provided with diametrically opposed longitudinally extending slots 19 in the wall thereof. Longitudinally movable within said sleeve18 is a lead projecting plunger 20, having oppositely extending lateral lugs -0r ears 21, which are respectively engaged within saidslots 19, so that when said shell 14 and the sleeve, 18 affixed thereto arc turned axially, saidplunger will turn therewith, while nevertheless remaining free for longitudinal movement relative thereto. a The upper end oflsaid plunger 20, above said lugs or ears 21, is formed to provide a spirally threaded section 22. Fixed withinusaid pene cil body 10 is nut-piecez23 with which said-threaded section 22 of the plunger-.20 is operatively engaged, as shown in Figure '3 of the drawings. By meansof the above described plunger structure, when the. pencil body 10 orthe shell 14 are turned axially'in relation one to the other, the threaded section will screw through the nut-piece 23 causing the plunger 20 to move longitudinally to thereby adjust the projection of the lead 16 from said shell 14, all in the manner readily to be understood from the above description and an inspection of said Figure 3 of the drawing more particularly. The above described pencil lead adjusting means is not, per se, claimed by me, but is illustrative of one of many types of pencil lead controlling or adjusting means common to magazine or mechanical pencils. So far as my present invention is concerned I merely desire to claim, broadly, a pencil lead adjust ing means in combination with the novel folding pencil compass structure for the purpose of adjusting the lead relative to the center point of the foldable compass leg element thereof, when the latter is unfolded and extended for use.

The foldable leg of my present form of pencil compass comprises a main leg section 24 and a foldable section 25 having at its free end a center point 26. Said main leg section 24 is provided at its upper end with a perforate hinge leaf 27, adapted to be received in the bearing or joint slot 12 of the bifurcated bearing block 11 of the pencil body 10, and thereupon pivotally connected with the latter by means of a pivot pin 28. Since it is desirable in a compass instrument that the respective legs thereof, when spread for use to give relative positions, should maintain such positions against accidental displacement or collapse, I have provided in connection with the interconnecting joint thereof an improvedmeans for frictionally binding or locking the same against displacement. To such end the outer sides of said bifurcated bearing block 11 are formed to provide flat faces 29 in parallel plane with said bearing or joint slot 12. A yoke member 30 having laterally spaced yoke-arms 31 is caused to embrace said bifurcated bearing block 11, so that said yoke-arms 31 are respectively engaged on opposite faces 29 of the latter. Said pivot pin 28 is provided at one end with an enlarged head 32 and at the opposite end with a threaded shank 33 of reduced diameter. One of said yoke-arms 31 is provided with an internally threaded perforation into which said shank 33 is en gaged when the pivot pin is assembled, thus pivotally uniting the parts together. Formed in connection with said bifurcated bearing blockll atthe inner or lower end of each face 29 is an arcuate shoulder 34-, and each yoke-arm,21 terminates in a nosing 35, as shown most clearly in Figure 5 of the drawings. The curve of said shoulders 34 is eccentricto the arc of movement of said nosings 35 about the pivot pin 28 as a center, and consequently, when the pencil leg and compass leg are spread apart, the rotation of said eccentric shoulders 34 relative to the nosings 35 tend to exert opposite longitudinal movement of the bifurcated bearing block 11 and hinge leaf 2'? relative to the yoke-arms 31 of the yoke member 30, thereby producing a shearing movement relative to the pivot pin 28 which results in a very strong frictional binding effect of the parts relative to the latter, which'tends to increase in proportion to the divergent distance at which the said legs are spread apart. It will thus be apparent that the adjusted legs will be adequately locked against displacement from desired spread apart relation when using the device as a compass, while nevertheless permitting desired movement of thevparts to open or close the same when the frictional resistance thus set up is relaxed by swinging the yoke member 30 into line with the pencil body 10 to move the nosings 35 back to centrally aligned normal relation to said shoulders 84. The outer end of said yoke member 30 is preferably of tubular form to detachably receive a head-piece or cap 36. Said cap is adapted to hold a rubber eraser member 8,7. It will be understood that the eraser member may be omitted, and the end of said yoke-member 3O finished with a permanent cap, if desired.

The main leg section 24 of the foldable leg element is provided with a longitudinal chamber 38 open along its inner side. The free end of said main leg section 24 is provi ded with a tapered bearing slot 39, the sides of which are slightly convergent from the outer end thereof toward the inner end of the same, The foldable section 25 is suitably formed or shaped, and is provided at its inner end with a perforate tapered or wedgeshaped hinge leaf 40, the sides of which are slightly convergent from its outer end toward the inner end thereof, so that when said foldable section is folded back upon and into the chamber 38 of'said main leg section 24, said hinge leaf 40 will conform to the normal conformation of the tapered-bearing slot 89, as shown in Figure 6. A suitable pivot pin M is passedv laterally through the thus engaged ends of said main leg section 24; and foldable section 25 to pivotally' unite the same. When, however, said foldable'section 25 is out-turned or swung into operative extended relation to said main leg section 24, as shown in Figures l, 7 and 8, said tapered or wedge-shape hinge leaf 40 will be longitudinally reversed relative to said tapered bearing slot 39, and in thus turning, the widened part of the wedgeslike hinge leaf 40 will be caused to enter the narrowing part of the bearing slot 39, thereby exerting a lateral pressure producing a strong frictional engagement of the former with the sides of the latter, operating to bind or hold the leg sections against accidental. collapse from their operative extended relation. Formed at the juncture of said hinge leaf 40 with the body of said foldable section 25, and at each side of said hinge leaf, are laterally disposed shoulders 42 which, when said foldable section is unfolded and aligned in extended relation to said main section 24 will abut the end of the latter andthus limit the outward turning or unfolding movement of said foldable section 25. I

As will be evident from an inspection of the accompanying drawings, the comp-ass leg'may be flushly folded and concealedin the pencil leg by, first, folding the foldable section 25 over upon and into the main section 24, and thereupon, in turn,'swinging the main section 24 through the opening 13 into the hollow interior of the pencil body 10. It will be apparent that a very neat and compact arrangement results, whereby the device will normally have the appearance of and may be employed as an ordinary pencil, but which, when the compass leg is unfolded and extended, quickly converts the pencil into a very practical and useful drafting compass instrument.

In order to facilitate the unfolding manipulation of the compass leg, the sides of the main section may be provided with thumb-nail nicks 43, and the pencil body 10 with depressed portions or notches 44 bordering the margins of the opening 13, and with which said thumb-nail nicks 43 register when the compass leg is folded into the pencil body. To assist in manipulating the foldable section 25 of the compass leg relative to the main section 24 thereof, the walls of the latter bordering the chamber 38 may be provided with clearance notches 45 to permit the infolded section 25 to be engaged or grasped by the fingers.

Having thus described my present invention, I claim 1. In a device of the kind described, ,comprising a pencil body having an opening along its side; a foldable compass leg pivotally connected with the upper end ofsaid pencil body adapted -to .be folded upon itselfand swung through said opening of said pencil body to flushly conceal the same within the latter; the combination of a yoke .member having yoke-arms to embrace said upper end of said pencil body; a pivot pin laterally engaged through said yoke-arms,

pencil body end and compass leg; and said pencil body end having laterally arcuate shoulders eccentric to the pivot pin and engageable by the free ends of said yoke-arms for the purposes described.

2. In a device of the kind described, com prising a pencil body having an opening along its side; a foldable compass leg having a hinge leaf at its upper end; the combina- 'pivotally ing block over its flat faces; a'pivot pin laterally engaged through said yoke-arms, bifurcated bearing block and hinge leaf to pivotally unite said yoke member, pencil body and compass leg together; said yokearms having nosings at their free ends; and

said bearing-block having external laterally arcuate shoulders eccentric to the pivot pin and of a radius less than that ofthe arc of movement of said nosings aboutsaid pivot pin, said shoulders being engageable by said nosings for compass leg being adapted to be folded upon itself and swung through said opening of said pencil body to flushly conceal the same within the latter.

3. In a device of thekind described,comprising a hollow pencil body having a lead holding and adjusting means at its free end, said pencil body having an opening along its side; afoldable compass leg comprising connected upper and lower sec tions, said lower section being adapted to be folded back upon said upper section; said upper section having a hinge leaf atits upper free end; the combination of a bifurcated bearing block at its upperend providing a joint slot'in whichsaid hinge leaf is'engaged, said bifurcated bearing block having fiat faces on its opposite exterior sides; a yoke-member having yoke-arms to straddle said bearing block over its flat faces; a pivot pin laterally engaged through said yoke-arms, bearing block and hinge leaf; said yoke-arms having nosings at their free ends; and said bearing block having external laterally arcuate shoulders eccentric to the pivot pin and of a radius less than that of the arc of movement of said nosings about said pivot pin, said shoulders being engageable by said nosings for the" purposes described; said compass leg being adapted to' be folded upon itself the purposes described; said and swung through said opening of said "pencil body to flushly conceal the same within the latter.

In testimony that I claim the invention set forth above I have hereunto set my hand August, 1926. 

